Photographic speed increasing and latent image stabilizing compounds

ABSTRACT

Photographic silver halide emulsions show increased speed and reduced latent image fading when a compound of the following structure is incorporated: ##STR1## wherein: X is ##STR2## Y 1  and Y 2  individually represent hydrogen or an aromatic nucleus or together represent the atoms completing a fused aromatic nucleus; 
     Z is ##STR3## R is hydrogen or lower alkyl of from 1 to 5 carbon atoms; and R 1  is hydrogen or methyl.



